Washington Revised Code Title 7. Special Proceedings and Actions § 7.70.030. Propositions required to be established--Burden of proof

(1) That injury resulted from the failure of a health care provider to follow the accepted standard of care;

(2) That a health care provider promised the patient or his or her representative that the injury suffered would not occur;

(3) That injury resulted from health care to which the patient or his or her representative did not consent.

Unless otherwise provided in this chapter, the plaintiff shall have the burden of proving each fact essential to an award by a preponderance of the evidence.